This invention relates to tray formations which are particularly useful in connection with the packaging of food products and is more particularly concerned with improvements in a tray construction which will serve as a leakproof container for products in liquid or semi-liquid form and which may be fabricated of paperboard with a coating of heat resistant material so as to be capable of withstanding, without breakdown, the temperatures encountered when heating or processing in a high frequency oven, a heating bath or a heating plate.
Trays have been designed heretofore which are adapted for use in the food industry where it is desired to package products which are in various forms and various stages of processing so that the product can remain in the tray while it is processed or while the processing is completed in an oven, hot bath, or the like, and then consumed, with the tray serving as a convenient serving dish. Generally, these trays have been formed of a metal foil which will withstand the temperature necessary to process the product. Some efforts have been directed toward providing tray structures formed from non-metal materials which are sufficently heat resistant for oven processing. One such tray arrangement is described in U.S. Pat. No. 3,550,835 granted Dec. 29, 1970.
Many of the prior containers of this type have not proven entirely acceptable for one reason or another. Some of them have not been designed so as to provide a leakproof construction enabling the packaging of a fluid product in a satisfactroy manner. Some of them have not been satisfactory as a serving dish. Others have been too costly for disposable use or have required special machinery for their fabrication which has increased the cost to an objectional degree.
It is a general object of the present invention to provide an improved tray type packaging container which may be formed of a foldable sheet material capable of withstanding temperatures encountered in various food processing equipment, which is leakproof, sufficiently sturdy to permit substantial stacking, more economical to manufacture and more satisfactory for use as a serving dish than similar containers heretofore provided.
It is a more specific object of the invention to provide a tray type container which is formed from a single blank of paperboard or other suitable sheet material wherein a generally rectangular bottom wall is joined to upstanding sidewalls by relatively narrow outwardly bowed sections of material and the sidewalls are connected to each other at their opposite ends by integral web sections having inwardly bowed inner faces and forming relatively rigid corner posts.
Another object of the invention is to provide a tray type container which may be formed of a single blank of paperboard material, or the like, and which comprises a generally rectangular bottom wall connected to the bottom portions of upstanding sidewalls by outwardly bowed segments of the material extending between spaced score lines and having sidewalls connected to each other at their opposite ends by integral web structures with a generally rectangular main portion, the bottom edge of which is defined by an inwardly curved score line which connects the score lines of the adjoining sidewall panels.
A further object of the invention is to provide a tray of the character described for containing a food product, or the like, which is characterized by a generally rectangular bottom wall with upstanding peripherial sidewalls wherein the material at the juncture of the sidewalls with the bottom wall, and with each other, is formed, so as to provide the tray with curved or rounded interior surfaces.
Another object of the invention is to provide a tray, of the character described, which is fabricated from a single blank of foldable sheet material, wherein the blank is scored to form a bottom wall panel and adjoining sidewall panels which are separated from the bottom wall panel by double score lines spaced to provide a rounded corner edge when the sidewall panels are hinged to upright position relative to the bottom wall panel and corner connecting webs defined by score lines which have a curved configuration at the bottom ends for connecting the double score lines of the adjoining panels.
A still further object of the invention is to provide a tray type container structure, of the character described, wherein the tray may be fabricated from a single cut and scored blank of foldable sheet material by employing normal folding techniques.
To this end the invention, as disclosed and claimed herein, comprises a tray type container formed from a single blank of foldable sheet material which includes a bottom wall and peripherial sidewalls upstanding from the margins of the bottom wall and integrally joined at adjacent ends by post forming foldable web members which are contoured to afford a curved edge connection with the bottom wall and with curved hinge areas connecting the sidewalls and the bottom wall.
The aforesaid and other objects and advantages of the invention will become more apparent upon consideration of the preferred form of the tray construction which is illustrated in the accompanying drawings wherein like parts are identified by the same numerals throughout the views.